Originally thought to be a quasi-satellite of Pluto, scientists now say 1994 JR1 is a Kuiper Belt object that is a distant remnant of the early solar system.
NASA’s New Horizons spacecraft has discovered a 90-mile-wide Kuiper Belt object (KBO) orbiting beyond Pluto, more than 3 billion miles away from the sun. According to NASA, the object is a distant remnant of the early solar system. Scientists hope to further explore this strange new world and others like it in future extended missions.
1994 JR1 has been observed twice now, first in November 2015 and, more recently, on April 7 and 8. The first sighting was from 170 million miles away. The April viewing was from only 69 million miles. Images were taken with New Horizons’ Long Range Reconnaissance Imager (LORRI).
New Horizons science team member Simon Porter said the observations include valuable findings. “Combining the November 2015 and April 2016 observations allows us to pinpoint the location of JR1 to within 1,000 kilometers (about 600 miles), far better than any small KBO.” Determining a more accurate location of JR1’s orbit also allows the team to dispel a theory from several years ago that the KBO is a quasi-satellite of Pluto.
The closer vantage point allowed the science team to determine that JR1 rotates once every 5.4 hours, which is a JR1 day. According to team member John Spencer, “That’s relatively fast for a KBO.” Spencer also said that the JR1 observations are good practice for close-up viewing of 20 more ancient KBOs. That mission will come in the next few years if NASA approves it.
The Kuiper Belt is a ring of ice debris and rock encircling our solar system. Porter says that the cold classical objects found in the Kuiper Belt are “the most primordial objects.” “They were never pushed around by the giant planets; they’re pretty much where they formed and haven’t been disturbed except for occasionally bumping into each other.” “Cold classical” does not refer to temperature, but rather to orbits, which are not close to anything else.
Cold classical objects have never been visited before, so the new mission, if NASA funds it, could provide valuable information about how our solar system formed 4.6 billion years ago. No one knows what the Kuiper Belt objects are made of, or the surface geology or topography. “We’ve never been to one of these objects before, so we really have no idea what it’s like,” says Porter.
The first close-up observations of Pluto and its five moons occurred when New Horizons flew through the system on July 14, 2015. The spacecraft should closely pass by 2014 MU69, another Kuiper Belt object , on Jan. 1, 2019. MU69 is too far away and too small to reveal its details through ground observation, even with the Hubble telescope.
Although New Horizons has already pointed its trajectory toward MU69, approval of the mission extension needs to come from NASA. If the mission is not approved, Porter says NASA will “literally turn off the spacecraft” this year.
Leave a Reply